1. Field of the Invention
The present invention relates to a pallet assembly.
2. Background Art
Pallets formed of molded plastic material have distinct advantages over those made of wood or metal. While wood pallets have sufficient stiffness, they are heavy; are subject to warpage, splintering and splitting; are nonuniform in strength; and gain significant weight when wet. Metallic pallets typically are expensive and, in the case of steel, heavy and subject to corrosion. Plastic pallets are stronger, lighter and more durable than wooden pallets. Heretofore, fire retardance as it relates to plastic pallets has not been recognized as an issue. However, recently, plastic pallets have been the subject of standards promulgated by the National Fire Protection Association (NFPA), Underwriters Laboratories Inc. (UL), Factory Mutual Research Company (FMRC), and National Association of Fire Marshals.
Some standards allow for plastic pallets to be used the same as wood pallets when experimental data show equivalency in the burning and suppression characteristics between the plastic and wood pallets. Unfortunately, some material presently used to help promote fire retardance in plastic pallets, such as an engineered resin blend of high-impact polystyrene and polyphenylene oxide, is very expensive and thus not cost efficient to mold an entire pallet from this material. Such material may also not be as injection-molding friendly as other polymeric materials.
Therefore, a pallet is desired which is accepted by the fire community as having burn and suppression properties substantially similar or better than wood, is relatively inexpensive, lightweight, and easy to manufacture.